Detergents for use in laundering



Patented Feb. 15, 1938 DETERGENTS FOR USE LAUNDERING- PROCESSES Walter H. McAllister, Wyoming, Ohio, assignor to The Procter & Gamble Company, Cincinnati, Ohio, a corporation of Ohio No Drawing.

13 Claims.

This invention relates to the preparation of useful detergents from sulfated products lacking in detergency and derived mainly from secondary alcohols, from olefines, or from the un- Application April 17, 1935, Serial No. 16,815

saponifiable oxygen-containing fraction of oxidized petroleum hydrocarbons.

Essentially my invention consists first in the discovery that there are usually associated with the active constituents of these products as ordinarily produced certain other substances which act not merely as inert diluents, but which have an actual anti-sudsing and anti-detergent action; and, secondly, that when these particular antibodies are removed, the remaining sulfated sub- 2 While the most commonly used detergent material has always been soap in its various forms,

that is, the water-soluble salts of higher aliphatic carboxylic acids, various other detergent substances have come into use during recent years,

particularly the water-soluble salts of the sulfuric esters of normal primary alcohols containing from ten to about twenty-two carbon atoms per molecule and certain other sulfated or sulfonated esters or other compounds having about the same number of carbon atoms per molecule. Many of these materials are very eflicient detergents and are greatly superior to soap in the respect that they work almost equally well in either hard or soft water. The normal primary alcohols here referred to, are usually obtained by 35 reduction of fatty oils, either by high pressure hydrogenation or by other means.

This invention is concerned with the water-soluble'salts of theproducts of the reaction of a sulfonating agent on: secondary aliphatic alcohols,

. 40 olefines, products derived from the partial oxidation of petroleum hydrocarbons, and mixtures of these substances, regardless of their source,

and particularly this invention is concerned with the soluble salts of sulfuric acid esters so obtained. 45 It should be understood that all the detergent producing bodies mentioned herein have about ten to twenty-five carbon atoms in the organic radical unless otherwise stated.

In my copending application Ser. No. 7,583, filed February 21, 1935, I have described a particular practice as applied to primary or secondary suli'onated alcohols and allied substances above named for purification thereof. In the present application I cover that aspect of my invention which includes said practice as well as others as applied to the said secondary alcohols and allied substances.

Many attempts have been made to produce sulfated detergent bodies from cheap sources such as petroleum in particular, but up to this 5 time the results have not been very satisfactory. The partial oxidation of petroleum under suitable conditions results in the formation of a mixture of various classes of substances such as carboxylic acids, ketones, alcohols,' and other 10 bodies. When the oxygen containing portion of this mixture is saponified, acidified, and the carboxylic acids separated, there remains a mixture containing a preponderating proportion of secondary alcohols together with minor proportions I of other substances. Primary alcohols if present are in only minor proportions. When this mixture is sulfated and neutralized in the same manner that the primary alcohols from reduction of fatty oils are sulfated and neutralized, there results a product which is of little or no value as a detergent, in spite of its high content of sulfated secondary alcohols, in which respect it differs markedly from the corresponding primary alcohol product.-

Olefines when sulfated and neutralized likewise show little or no detergent power as ordinarily produced. Olefines may be obtained from various sources, such as from petroleum, from dehydration of fatty alcohols, from the electrolysis'of soap solutions, as has been recently proposed, in which latter case a mixture believed to consist mainly of olefines and secondary alcohols results.

I have discovered that th soluble salts of the sulfatedsecondary alcohols nd sulfated olefines when free from unsuifated organic impurities or nearly so have excellent sudsing and detergent ample, to the purifled'soluble salts of sulfated secondary alcohols and have noted a marked harmful efiect on the sudsing and detergent properties of the sulfate salt. This is indeed strange since the presence or addition of a small amount, say five to ten per cent, of unsulfated alcohol,

either primary or secondary, to a soluble salt of a sulfated primary alcohol, on the contrary, causes a very definite improvement in both sudsing and detergency. Other unsulfated and unsulfatable bodies also usually occur mixed with sulfated secondary alcohols and olefines, and these materials in general are worse than mere inert diluents because of their destructive effect on sudsing and detergency. When, however, these unsulfated secondary alcohols, and unsulfatable materials present in products of the oxidation of the hydrocarbons, and the by-products of sulfonation, are removed, then I find that the resulting products have good detergency, entirely suitable for use in regular laundering work.

Inasmuch as these sulfated products from secondary alcohols and olefines consist largely of compounds having the polar or water-solubilizing group attached to a carbon atom other than the terminal carbon, it has been quite generally believed that the soluble salts produced from such compounds were inherently and necessarily inferior in detergent properties to the soluble primary alkyl sulfates in which latter the polar group is attached at the end of the chain of. carbon atoms. My discovery, however, demonstrates that this belief is erroneous and that the chief cause of the deficiency of the sulfated secondary alcohols and olefines, as hitherto pro duced, is the presence of certain bodies having definitely anti-sudsing and anti-detergent action on these classes of sulfated compounds, and that the removal of the anti-bodies results in producing good detergents which work well both in hard and in soft water. I find, further, that in order to produce good detergents it is not sufficient to separate the unsulfatable materials, such as unoxidized hydrocarbons, ketones, etc., from the secondary alcohols, etc., before sulfation, because there are usually formed certain other byproducts during sulfation which also have a destructive action on the detergency, and furthermore a portion of the secondary alcohols or olefines remains unsulfated. Consequently, it is essential to remove the anti-bodies and any inert organic impurities after sulfation and neutralization in order to obtain the best results. While it is essential. thatsubstantially all the unsuifated secondary alcohols, ketones, olefines, other hydrocarbons, and other organic material, should be removed as completely as possible, the presence of moderate amounts of inorganic salts such as sodium sulfate or sodium chloride has little effect on the resulting sudsing and detergency.

It should be pointed out at this place that in determining the value of. a detergent product for practical use in laundering, several factors must be considered, such as the volume of suds produced by a given quantity of the detergent, the stability or lasting quality of the suds, especially in the presence of soiled fabrics and. thirdly, the actual detergent or cleansing power.

These are different properties which are not necessarily associated simultaneously in the same product, but all are of importance in making a good and satisfactory detergent.

Preferably, I prepare the detergents for use in laundering or cleansing processes in the following manner: The alcohols (mainly secondary) and/or olefines, or mixtures containing the alcohols and/or olefines, purified or unpurified, are subjected to suitable treatment with sulfuric acid, chlorsulfonic acid or other sulfating media in the known way. The alkyl sulfuric acids thus formed are neutralized with sodium hydroxide, potassium hydroxide, ethanolamines, or some other base which forms water-soluble salts with the alkyl sulfuric acids, after which the neutralized products are separated from tlie'unsulfated organic materials or other organic impurities.

I find that it is possible to remove most types of harmful organic impurities in a number of ways, as, for example: first, by distillation during drum or spray drying of the secondary alkyl sulfate salt; second, by crystallization from a solvent such as ethyl alcohol, propyl alcohol, acetone or methyl alcohol, thereby leaving the harmful organic materials in the solvent; third, by washing the dried product with ethyl ether, petroleum ether or other fat solvent; fourth, by extraction with petroleum ether from a water-ethyl alcohol solution of the product. Other fat solvents than petroleum ether which are substantially insoluble in the aqueous-alcohol solution, such as carbon tetrachloride, chloroform, or other chlorinated hydrocarbons, toluene, benzine, benzol or other hydrocarbons, may be used, and other watersolubl aliphatic monohydric alcohols than ethyl alcohol, such as methyl, propyl or isopropyl alcohol, may be used to prevent emulsions, as described in my copending application Serial No. 7,583. Any one, or a combination of two or more, of the means for removal of the impurities may be found most suitable in individual cases. This invention is not limited'to the use of. any particular method of removing organic impurities from the sulfated products; it is intended to cover broadly any means of preparing detergents for use in laundering or cleansing processes which means includes the step of removing unsulfated organic materials or other harmful materials from the sulfated products obtained from secondary aliphatic alcohols, olefines, and the unsaponifiable oxygen-containing fraction of oxidation products from paraflin hydrocarbons.

It should furthermore be understood that the present invention is not limited to the specific examples given in this specification but that it includes purified sulfated secondary alcohols or olefines coming within the whole tenor of the specification and the terms of the claims. Also, the limitation of the claims to sulfuric acid esters of the alcohols or salts thereof is not to exclude from their scope products containing a minor portion of true sulfonic acids or salts thereof.

, Example 1 Parafiin wax melting at 47-49 G. was subjected to oxidation by passing a current of air through the wax at to C., the reaction vessel being loosely filled with pieces of porcelain. The quantity of air employed was 100 liters per hour per each 100 grs. of parafiin wax and the oxidation was stopped when it was thought that about 50 per cent of the initial material, had been oxidized to oxygen-containing organic compounds. "I'he' reaction mixture was treated with about 10 times its weight of methanol, whereupon most of the unoxidized hydrocarbons remained undissolved and most of the oxygen-containing compounds dissolved in the methanol. The resulting soluti'oii was separated from the non-oxidized part by filtration at room temperature. The residue obtained by evaporation of the solution amounted to about 50 per cent of the initial material and had a saponification value of 210.

The oxidized portion was saponifled with caustic soda. solution and the unsaponiflable material separated from the soap solution by extraction with petroleum ether from a solution of the soap containing approximately equal volumes of ethyl alcohol and water and recovered by evaporation of the-petroleum ether. One part of 10 per cent oleum (fuming sulfuric acid) was stirred into 3 parts of this unsaponifiable portion of the oxygen-containing compounds at about 35 C. and the resulting sulfated product neutralized by stirring into 4 parts 17 per cent sodium hydroxide solution. Up to this point the practice outlined is not original with me. My practice relates to the converting of the said resulting sulfated product into an excellent foaming, sudsing and, detergent agent.

To 100 parts of this impure neutralized sulfated product, 150 parts denatured ethyl alcohol and 150 parts of water were added and the resulting solution extracted 5 times with petroleum ether, using about 100 parts of petroleum ether for each extraction. Upon removal of the alcohol from the solution by evaporation, the thus purified sulfated product dissolved to a clear solution in water and was a good detergent, remarkably superior in this respect to the impure product, which latter did not dissolve to a clear solution in water and in concentrations ordinarily used in cleansing processes, failed to wash soiled cloths even as white as water alone.

Example 2 by crystallization of the latter from denatured ethyl alcohol, then drying and washing the crystallized product with ethyl ether. Whereas the untreated neutralized sulfated product, which I do not claim to be novel with me, was practically devoid of detergent properties, the treated product was a good cleansing agent. In laundering operations involving treatment of soiled muslin with dilute solutions of the treated product in hard water, excellent results were obtained the washed cloth being soft and clean.

Example 3 I used a fraction of the product prepared by liquid phase oxidation of parafiin wax followed by catalytic pressure hydrogenation of the oxygenated compounds from the product (to convert carbonyl compounds to alcohols) which had .a boiling point. between 70 and 195 C. under 2 mm. pressure and had a hydroxyl value of 209. Treatment of this fraction at 35 C. with the theoretical amount of chlorosulfonic acid to convert each hydroxyl group to a sulfuric ester group and then neutralization of the alkyl'sulfuric acids by pouring into sodium hydroxide solution, yielded a product which exhibited too little detergent value to be useful in laundering clothesor washing dishes. product employed is not novel with me.

parts of this neutral sulfation reaction Here, again, 7 the mixture was then dissolved in a mixture of about 200 parts water and about 200 parts denaturedethyl alcohol, and extracted five times with parts petroleum ether for each extraction. The organic impurities removed by the petroleum ether amounted to 37 per cent of the organic raw materials used for the sulfation and had a hydroxyl value of only 25. The denatured alcohol was removed from the solution of the treated sulfated material by steam distillation, and the 100 parts of a product prepared by electrolytic oxidation of the potassium soap of hydro genated coconut oil by the method of my copending application Ser. No. 645,478, filed December 2, 1932 now U. S. Patent No. 2,022,894 and having a hydroxyl value of 92 and an iodine value of 58, were sulfated by treatment with 75 parts 96 per cent sulfuric acid. The product was neutralized with sodium hydroxide. The neutralized material was then dissolved in equal parts of water and denatured ethyl alcohol and extracted five times with petroleum etheras in Example 2. The harmful organic constituents recovered from the petroleum ether amounted to 43 percent of the weight of the organic raw material used for the sulfation. Although the untreated sulfated product lacked sufiicient cleansing or detergent power for practical use, the treated product was entirely adequate and eflicient in this respect. This product, prepared from a mixture of oleflnes with the double bond at the end of the chain, and of alcohols which were predominantly secondary as shown by the Hell reaction, consisted mainly of salts of sulfuric esters, but was found to contain also an appreciable amount of sodium alkyl true sulfonates,

In the claims the word extracting" is employed to denote the removal of undesirable impurities by any of the four methods previously discussed, that is, distillation, crystallization of the neutralized secondary alkyl sulfate from organic solvent in which the unsulfated matter and other organic impurities are more soluble than the secondary alkyl sulfates, washing the dried neutralized product with a fat solvent, and treatment of an aqueous alcohol solution of the neutralized product with a fat solvent whereby the organic impurities and secondary alcohol sulfates are separated. The above useof the word extracting, is clearly within the accepted dicti'onary definition of same as given, for example, in Webster's New International Dictionary, Second Edition, unabridged.

Furthermore, reference to laundering agents herein is not meant to refer to any substance employed in a laundering operation besides de-' tergents, but rather is meant to refer only to the detergentsemployed in laundering processes.

Having thus described my invention, what I claim as new and desire to secure by Setters Patent is 1. A process of preparing a detergent suitable for laundering processes comprising extracting organic unsulfated material and other organic impurities from a product containing watersoluble salts of alkyl sulfuric acids obtained from soluble salts of alkyl sulfuric acids obtained irom olefines having ten to twenty-five carbon atoms in the molecule.

3. A process of preparing a detergent suitable for use in laundering processes comprising extracting organic unsulfated material and other organic impurities from a product containing water-soluble salts of suifated secondary alcohols and obtained by the sulfation and neutralization of the unsaponifiable oxygen-containing material resulting from the liquid phase oxidation of paraflin hydrocarbons.

4. The process of preparing a detergent suitable for use in laundering processes comprising extracting organic unsulfated material and other organic impurities from a product containing water-soluble salts of a member of the group of secondary alkyl sulfuric esters consisting of sulfated secondary alcohols, sulfated olefines, and the sulfated unsaponifiable oxygen-containing fraction resulting from the liquid phase oxidation of parafiin hydrocarbons, said members having ten to twenty-five carbon atoms in the organic radical.

5. The process of preparing a detergent suitable for use in laundering processes which comprises removing the free and combined carboxylic acids from the mixed oxygen-containing compounds in oxidized paraffin hydrocarbons, subjecting the product resulting therefrom and containing secondary alcohols to the action of a sulfating agent, neutralizing the sulfated material to form watersoluble salts from the alkyl sulfuric acids produced, and subjecting the neutralized material to the action of an organic solvent in which the unsulfated material and other organic impurities are more soluble than said salts.

6. The process oi preparing a detergent suitable for use in laundering processes which comprises removing the free and combined carboxylic acids from the mixed oxygen containing-compounds in oxidized paraflin hydrocarbons, subjecting the product resulting therefrom and containing secondary alcohols to the action of a sulfating agent, neutralizing the suliated material to form water-soluble salts from the alkyl sulfuric acids produced, drying said neutralized material, dissolving same in an organic solvent in which the unsulfated material and other organic impurities are more soluble than said salts, and subjecting the neutralized material to crystallization from said solvent.

taining secondary alcohols to the action of a sulfating agent, neutralizing the sulfated material to iorm water-soluble salts from the alkyl sulfuric acids produced, adding to the neutralized material an organic solvent in which the unsuliated material and other organic impurities are more soluble than said salts, and crystallizing said salts from the said solvent. 7

8. The' process of preparing laundering reagents which comprises removing the free and combined carboxylic acids from the mixed oxygen-containing compounds in oxidized paraffin hydrocarbons, subjecting the product resulting therefrom and containing secondary alcohols to the action of a suliating agent, neutralizing'the sulfated material to form water-soluble salts, preparing an aqueous alcohol solution of the neutralized sulfated material and extracting the unsulfated and other organic impurities therefrom with a fat solvent which is substantially insoluble in the aqueous alcohol solution.

9. In the process of preparing a detergent suitable for use in laundering processes from the neutralize'd sulfated liquid phase oxidation product obtained from-paraflln hydrocarbons, the step which consists in extracting from said products unsulfated matter and other organic impurities soluble in a fat solvent.

10. A compound having excellent detergent properties for use in laundering processes, consisting essentially of a water-soluble salt of a a compound of the group of secondary allqll sulfuric esters consisting of sulfated secondary alcohols, suliated olefines, and the sulfated unsaponifiable oxygen-containing fraction obtained by the liquid phase oxidation of paraflln hydrocarbons, said salt being substantially free from unsulfated organic material and other organic impurities and having ten to twenty-five carbon atoms in the alkyl radical.

11. A compound having excellent detergent properties for use in laundering processes consisting essentially of a water-soluble salt of a sulfated secondary alcohol, said salt being substantially free from unsuliated organic material and other organic impurities and having ten to twenty-five carbon atoms in the alkyl radical.

12. A compound having excellent detergent properties for use in laundering processes consisting essentially of a water-soluble salt of a sulfated olefine, said salt'being substantially free from unsulfated organic material and other organic impurities and having ten to twenty-five carbon atoms in the alkyl radical.

13. A compound having excellent detergent properties for use in laundering processes consisting essentially of a water-soluble salt of the sulfated unsaponiiiable oxygen-containing fraction obtained by the liquid phase oxidation 01 paraflin hydrocarbons, saidsalt being substantially free from unsulfated organic material and other organic impurities and having ten to twenty-five carbon atoms in the alkyl radical.

WALTER H. McAILIS'I'ER. 

